Salivary glands as a model for craniofacial applications of gene transfer

Update on diabetes diagnosis and management

BACKGROUND

The American Diabetes Association has established recommendations for the testing of undiagnosed people. Once diagnosed, those with diabetes must strive to maintain a level of glucose control that results in a metabolism that approaches that of people without diabetes. The dentist also can provide risk-reduction strategies for people prone to develop diabetes, and refer patients with signs and symptoms suggestive of diabetes to physicians.

METHODS

The authors describe criteria for establishing a diagnosis of diabetes and for identifying people at high risk of developing the disease. A combination of approaches in the medical management of type 1 and type 2 diabetes mellitus is presented, along with target outcomes.

RESULTS

Patients with diabetes maintain a glycosylated hemoglobin value of no higher than 7 percent. New therapeutic research includes early clinical trials of islet cell transplantation and therapeutic cloning from human stem cells, which may provide an alternate source of insulin-producing islet cells and, thus, may offer a potential cure for diabetes.

CONCLUSIONS

Rigorous metabolic control of diabetes can be achieved through a combination of therapeutic modalities and the establishment and maintenance of target outcomes. The dentist can implement preventive strategies and refer patients with signs and symptoms suggestive of diabetes to physicians.

CLINICAL IMPLICATIONS

The dentist and physician must work together as a team to achieve rigorous metabolic control of diabetes in their patients.

Management of salivary hypofunction during and after radiotherapy

Salivary hypofunction, the most common complication of high-dose radiation therapy (RT) to the head and neck, has a significant impact on quality of life, and requires careful planning of long-term dental and oral care. This report documents the results and conclusions of an evidence-based literature review on multidisciplinary team management of salivary hypofunction during and after RT. An update is provided on the pathophysiology of salivary hypofunction during and after RT, and recommendations for clinical management. The paper presents aspects managed by dental professionals (use of cholinergic agonists and other saliva stimulants, prevention of hyposalivation-induced rampant caries, and use of saliva substitutes), as well as the role of the radiation oncologist in minimizing salivary gland damage (parotid-sparing RT; cytoprotectants). This summary includes basic science, translational and clinical research topics with respect to radiation-induced salivary hypofunction, and provides an evidence-based management algorithm.

Gene therapeutics in Sjögren's syndrome

Sjögren's syndrome (SS) is a complex autoimmune disorder, characterised by mononuclear cell infiltration of exocrine glands, principally the lacrimal and salivary glands. Both cellular, in the form of autoreactive immune cells, and humoral factors, such as autoantibodies, contribute to the expression of the disease. SS can also occur as a systemic disease affecting several organs, and approximately 5% of the patients develop malignant lymphoproliferation. Today SS is considered uncurable. The treatment available is only palliative, and the treatment goals are to manage symptoms and prevent or limit tissue damage. This may involve both local and systemic measures. However, the existing systemic treatment of chronic inflammatory autoimmune diseases has several limitations and unwanted side effects. In recent years the possibility to treat diseases with gene therapy has gained interest and has become a subject of investigation. Given the multitude of factors contributing to the pathogenesis of SS, gene therapy is a major challenge, but may elicit great benefits if successful. Keeping this in mind, the possibility for gene therapeutics in SS in general and potential targets for gene therapy are discussed.

Radiotherapy-induced salivary dysfunction

Dry mouth (xerostomia) is one of the most common complaints following radiation therapy (RT) for head and neck cancers. Notably, RT causes irreparable damage to salivary glands that increases the risk for severe and long-term oral and pharyngeal disorders. Several strategies in the treatment of head and neck cancers have been developed to prevent RT-induced salivary dysfunction while providing definitive oncologic therapy. These include salivary-sparing RT; cytoprotectants (such as amifostine); combination therapy of high-dose-rate intraoperative RT, external beam RT, plus a cytoprotectant; salivary gland surgical transfer; and gene therapy. Future research that incorporates biologic, pharmacologic, and technologic advancements that optimize therapeutic ratios and minimizes adverse oral sequelae is warranted.

Xerostomia and the geriatric patient

Saliva is essential for the preservation of oral-pharyngeal health, and disorders of salivary physiology are associated with numerous oral and pharyngeal problems, particularly in older people. Although salivary function is remarkably intact in healthy aging, medical problems, medications, and head and neck radiotherapy can cause salivary dysfunction and complaints of xerostomia among older people. Sjögren's syndrome, an autoimmune exocrinopathy, is the most common medical disease associated with salivary dysfunction. Medications with anticholinergic side effects will impair salivary output, and head and neck radiotherapy for cancer will cause permanent destruction of salivary glands. Treatments for salivary problems are based upon establishing a diagnosis, protecting oral and pharyngeal health, stimulating remaining glands, and replacing lost salivary fluids.

The impact of gene therapy on dentistry: a revisiting after six years

BACKGROUND

Gene therapy is an emerging field of biomedicine that has commanded considerable scientific and popular attention. The procedure involves the transfer of genes to patients for clinical benefit. Transferred genes can b e used for either reparative or pharmacological purposes.

OVERVIEW

In 1995, the first author and a colleague described the potential impact of gene therapy on dentistry, on the basis of initial studies of gene transfer applications to salivary glands, keratinocytes and cancer cells. Their conclusion was that gene therapy would have a significant impact on the nature of dental practice within 20 years. In this article, the authors consider research progress since 1995 and reexamine the earlier conclusion.

PRACTICE IMPLICATIONS

In the past six years, remarkable progress has been made in the field of gene therapy, including seven areas relevant to dental practice: bone repair, salivary glands, autoimmune disease, pain, DNA vaccinations, keratinocytes and cancer. While considerable problems remain, thus impeding the routine clinical use of gene transfer, gene therapy will have a pervasive and significant impact on areas of dental practice that are based in biological science. By 2015, this will translate into practitioners' having a wide range of novel biological treatment options for their patients.